KERATOACANTHOMA What are the aims of this leaflet? This leaflet has been written to help you understand more about keratoacanthomas (KAs). It tells you what they are, what causes them, what can be done about them, and where you can find out more about them. What are keratoacanthomas? KAs are relatively common benign skin growths from the cells surrounding the hair unit that usually appear in sun exposed skin. Clinically they can’t be easily differentiated from a more serious skin cancer, a squamous cell carcinoma (SCC). KAs grow quickly over the first few weeks but do not spread to other parts of the body. If left alone, they will usually go away by themselves in 4 to 6 months. What causes keratoacanthomas? Their precise cause is not known. Factors that may play a part include heavy sun exposure, contact with some chemicals, smoking, infection with some strains of wart virus, a suppressed immune system, and minor injuries to the skin. KAs are more common in fair than in dark-skinned individuals, and more so in men than in women. They are rare under the age of 20 and become more common with age. Are keratoacanthomas hereditary? Usually not, although multiple KAs are a part of a few rare inherited conditions. 4 Fitzroy Square, London W1T 5HQ Tel: 020 7383 0266 Fax: 020 7388 5263 e-mail:
[email protected] Registered Charity No. 258474 What are the symptoms of a keratoacanthoma? Usually there are none apart from their cosmetic appearance, as they tend to be on exposed skin. What does a keratoacanthoma look like? KAs occur more frequently on the face, and less often on the backs of the hands and forearms.